Such metal doors are known to the art and are primarily intended for use as fire doors. Thus, there is described in FI, C, 49 457 a fire door in which two mutually opposing planar panels are provided with resilient coupling members which extend along respective panels and which are intended to be snapped into one another, by displacing the one panel relative to the other. A similar snap-coupling arrangement is described in AT,B, 381 767.
SE,A, 8103482-9 describes a similar arrangement, in which the coupling members are formed by folding the outer ends of respective panels of the door leaf.
These known fire doors are made of steel and are relatively complicated in manufacture, particularly when desiring to vary the thickness of such doors. The aesthetic appearance of such doors is also impaired by at least one of the joints located along the side edges of the door, and hence doors of this known construction cannot be used in rooms where the door shall have a fully aesthetic appearance.
It is also impossible to use such door constructions readily in conjunction with double doors, in which the door leaf of one of the doors carries a mullion which cooperates with the other door leaf of the other door.
Further examples of doors constructed in accordance with prior art techniques are described in SE,C, 167 656, DE,C1 3 423 550 and FR,A 2,2 400 608.
One object of the present invention is to provide a metal door construction which avoids the aforesaid drawbacks and other drawbacks encountered with known metal doors and fire doors, while simplifying the manufacture of such doors and enhancing the flexibility thereof, and which will satisfy all requirements with regard to aesthetic appearance.